The laptop screen turns on properly then flickers and goes black. If you restart the laptop the failure sequence repeats.

Possible cause:

1. LCD screen inverter failure.
2. LCD screen backlight lamp failure.

Possible troubleshooting steps and repair solution:

When the laptop LCD screen flickers and goes black, most likely the problem is related either to the screen inverter or backlight lamp inside the screen.

You cannot tell which one is failing without testing the laptop with another working inverter or backlight lamp. Both parts have very similar failure symptoms.

If you have to guess, replace the inverter board first. If it doesn’t help to fix the problem, replace the LCD screen. It’s possible to replace just the backlight lamp inside the screen but it’s not easy and should be done by an experienced technician.

The laptop starts with a blank screen. The laptop stays on but no image appears on the screen even after a few minutes.

Possible cause:

1. Backlight failure.
2. Memory failure.
3. Motherboard failure.

Possible troubleshooting steps and repair solution:

First of all, take a closer look at the screen and make sure that the screen is really blank. Look under a bright light. If you can see a very faint image, most likely it’s either bad inverter or faulty backlight lamp. Try replacing the inverter board first and if it doesn’t help, replace the LCD screen.

In a case of the backlight failure, you still should be able to use the laptop with an external monitor attached to the VGA port.

If the screen is completely blank and has no image at all, check the memory modules. It’s possible that one of the modules has failed. Try reconnecting memory modules. If you have two modules installed, try removing them one by one. Test the laptop with each modules separately. Try replacing memory with another known good stick.

If manipulations with laptop memory do not help, it’s likely that your problem is related to the motherboard.

The laptop screen goes black for no reason. The laptop starts properly and the screen works properly for some time, but later it just goes black. After you restart the laptop, the screen goes black after some time again.

Possible cause:

1. Screen inverter failure.
2. Screen backlight failure.

Possible troubleshooting steps and repair solution:

Most likely this problem is related to the screen inverter failure. The inverter board works as a power supply for the backligh lamp. When inverter fails, the screen goes dark. You still can see a very faint image on the screen but it’s very dark. Try replacing the inverter board first. It’s located inside the display panel below the LCD screen.

If a new ivnerter doesn’t fix the problem and the screen still goes dark after some time, most likley you have a faulty backlight lamp inside the LCD screen. If that’s the case, you’ll have to replace the screen. It’s possible to replace just the backlight lamp but it’s not easy and should be doen only by an experienced technician.

When inverter or backligth lamp fails, you still should be able to use the laptop with video on the external monitor.

The laptop makes high pitched noise.

Possible cause:

1. Screen inverter failure.
2. Motherboard failure.
3. Hard drive failure.
4. Cooling fan failure.

Possible troubleshooting steps and repair solution:

1. Try reducing the screen brightness. If there is no noise when the screen brightness is reduced, most likely you have a faulty screen inverter board. In most laptops the inverter board is located inside the display panel below the LCD screen. Try replacing the inverter board.

2. Test your laptop with an external monitor. Set the laptop to output video only on the external monitor. If the high pitched noise is gone when there is no video on the laptop screen, again, most likley it’s related to the screen inveter.

3. If the laptop makes hight pitched noise even when there is no video on the screen, most likely you have a faulty component somewhere on the motherboard.You’ll have to replace the motherboard or use it as is.

4. A failing hard drive also can be the source of the very annoying hight pitched noise. You can remove the hard drive and boot your laptop from a live Linux CD (Knoppix for example). If the noise is gone when the hard dive is removed, most likely that’s your problem. If the noise is still there, it’s not related to the hard drive.

5. Could be a faulty cooling fan. If the noise appear only when the cooling fan is spinning, most likely you have a bad fan. Replace the fan.

The laptop starts but the screen remains very dark. You can hear normal startup sound even though the screen is almost black. If you look on the screen very closely under the bright light you can see outlines of normal desktop image.

Possible cause:

1. Inverter board failure.
2. Screen backlight failure.

Possible troubleshooting steps and repair solution:

1. Most likely this problem is related to the inverter board failure. The inverter board works as a power supply for the backlight lamp inside the LCD screen. When inverter fails, the laptop start normal but without backlight on the screen. As a result, the image on the screen is so dark that you can barely see the desktop image. You have a good chance to fix the problem by replacing the inverter board.

2. If a new inverter board didn’t fix it, most likely you have a faulty backlight lamp inside the screen. You can try replacing the backlight lamp but it’s not easy and should be done only by an experienced technician. Otherwise, replace the whole LCD screen.

The laptop screen works fine on startup but after a while the screen starts to flicker and goes dark. If you restart the laptop, the screen turns on as normal but later it starts flickering and goes dark again. Time intervals between screen failure may vary.

Possible cause:

1. Backlight lamp failure.
2. Inverter board failure.

Possible troubleshooting steps and repair solution:

1. If the screen flickers before it goes dark, most likely the problem is related to the backlight lamp which is mounted inside the LCD screen. You’ll have to replace the backlight lamp inside the screen (for advanced technicians only) or replace the whole screen.
2. Replace the inverter board.

If the screen just go dark without flickering, try replacing the inverter board first and after that replace the LCD screen (or backlight lamp).